<title>多边形</title><link href="http://hzoi.com/tomorrow.css" rel="stylesheet"><div class="ui existing segment"><pre><code><span class="pl-cp">#include</span> <span class="pl-cpf">&lt;cstdio&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span> <span class="pl-cpf">&lt;cstring&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span> <span class="pl-cpf">&lt;iostream&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span> <span class="pl-cpf">&lt;algorithm&gt;</span><span class="pl-cp"></span>
<span class="pl-k">using</span> <span class="pl-k">namespace</span> <span class="pl-n">std</span><span class="pl-p">;</span>
<span class="pl-k">typedef</span> <span class="pl-kt">long</span> <span class="pl-kt">long</span> <span class="pl-n">ll</span><span class="pl-p">;</span>
<span class="pl-cp">#define lson l, mid, rt &lt;&lt; 1</span>
<span class="pl-cp">#define rson mid + 1, r, rt &lt;&lt; 1|1</span>
<span class="pl-k">const</span> <span class="pl-kt">int</span> <span class="pl-n">maxn</span> <span class="pl-o">=</span> <span class="pl-mf">1e2</span> <span class="pl-o">+</span> <span class="pl-mi">10</span><span class="pl-p">;</span>
<span class="pl-k">const</span> <span class="pl-kt">int</span> <span class="pl-n">mod</span> <span class="pl-o">=</span> <span class="pl-mf">1e9</span> <span class="pl-o">+</span> <span class="pl-mi">7</span><span class="pl-p">;</span>
<span class="pl-kt">int</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">],</span> <span class="pl-n">b</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">];</span> 
<span class="pl-kt">int</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">][</span><span class="pl-n">maxn</span><span class="pl-p">],</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">][</span><span class="pl-n">maxn</span><span class="pl-p">];</span>
<span class="pl-kt">char</span> <span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">],</span> <span class="pl-n">d</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">];</span> 
<span class="pl-kt">int</span> <span class="pl-n">y</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">];</span>
 
<span class="pl-kt">int</span> <span class="pl-nf">main</span><span class="pl-p">(){</span>
	<span class="pl-kt">int</span> <span class="pl-n">n</span><span class="pl-p">;</span>
	<span class="pl-n">cin</span> <span class="pl-o">&gt;&gt;</span> <span class="pl-n">n</span><span class="pl-p">;</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">i</span><span class="pl-p">)</span>
		<span class="pl-n">cin</span> <span class="pl-o">&gt;&gt;</span> <span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-mi">1</span><span class="pl-p">]</span> <span class="pl-o">&gt;&gt;</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span>
	<span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">n</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-mi">0</span><span class="pl-p">];</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">i</span><span class="pl-p">){</span>
		<span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">n</span> <span class="pl-o">+</span> <span class="pl-n">i</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span> 
		<span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">n</span> <span class="pl-o">+</span> <span class="pl-n">i</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span>
	<span class="pl-p">}</span>
	<span class="pl-kt">int</span> <span class="pl-n">ans</span> <span class="pl-o">=</span> <span class="pl-o">-</span><span class="pl-mh">0x3f</span><span class="pl-p">;</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">x</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">x</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">x</span><span class="pl-p">){</span>
		<span class="pl-n">memset</span><span class="pl-p">(</span><span class="pl-n">dpmax</span><span class="pl-p">,</span> <span class="pl-o">-</span><span class="pl-mh">0x3f</span><span class="pl-p">,</span> <span class="pl-k">sizeof</span><span class="pl-p">(</span><span class="pl-n">dpmax</span><span class="pl-p">));</span>
		<span class="pl-n">memset</span><span class="pl-p">(</span><span class="pl-n">dpmin</span><span class="pl-p">,</span> <span class="pl-mh">0x3f</span><span class="pl-p">,</span> <span class="pl-k">sizeof</span><span class="pl-p">(</span><span class="pl-n">dpmin</span><span class="pl-p">));</span>
		<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-n">x</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">i</span><span class="pl-p">){</span>
			<span class="pl-n">b</span><span class="pl-p">[</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span>
			<span class="pl-n">d</span><span class="pl-p">[</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">c</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span>
			<span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">i</span> <span class="pl-o">-</span> <span class="pl-n">x</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">a</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">];</span>
		<span class="pl-p">}</span>
		<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">l</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">l</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">l</span><span class="pl-p">){</span>
			<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">+</span> <span class="pl-n">l</span> <span class="pl-o">-</span> <span class="pl-mi">1</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">i</span><span class="pl-p">){</span>
				<span class="pl-kt">int</span> <span class="pl-n">j</span> <span class="pl-o">=</span> <span class="pl-n">i</span> <span class="pl-o">+</span> <span class="pl-n">l</span> <span class="pl-o">-</span> <span class="pl-mi">1</span><span class="pl-p">;</span>
				<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">k</span> <span class="pl-o">=</span> <span class="pl-n">i</span><span class="pl-p">;</span> <span class="pl-n">k</span> <span class="pl-o">&lt;</span> <span class="pl-n">j</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">k</span><span class="pl-p">){</span>
					<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">d</span><span class="pl-p">[</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">==</span> <span class="pl-sc">&#39;t&#39;</span><span class="pl-p">){</span>
						<span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">+</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span>
						<span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">min</span><span class="pl-p">(</span><span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">+</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span>
					<span class="pl-p">}</span> <span class="pl-k">else</span> <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">d</span><span class="pl-p">[</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">==</span> <span class="pl-sc">&#39;x&#39;</span><span class="pl-p">){</span>
						<span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">*</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span> 
						<span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">*</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span> 
						<span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">min</span><span class="pl-p">(</span><span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">*</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span> 
						<span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">min</span><span class="pl-p">(</span><span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">],</span> <span class="pl-n">dpmin</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">k</span><span class="pl-p">]</span> <span class="pl-o">*</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-n">k</span> <span class="pl-o">+</span> <span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]);</span> 
					<span class="pl-p">}</span>
				<span class="pl-p">}</span>
			<span class="pl-p">}</span>
		<span class="pl-p">}</span>
		<span class="pl-n">y</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">n</span><span class="pl-p">];</span> 
		<span class="pl-n">ans</span> <span class="pl-o">=</span> <span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">ans</span><span class="pl-p">,</span> <span class="pl-n">dpmax</span><span class="pl-p">[</span><span class="pl-mi">1</span><span class="pl-p">][</span><span class="pl-n">n</span><span class="pl-p">]);</span>
	<span class="pl-p">}</span>
	<span class="pl-n">cout</span> <span class="pl-o">&lt;&lt;</span> <span class="pl-n">ans</span> <span class="pl-o">&lt;&lt;</span> <span class="pl-n">endl</span><span class="pl-p">;</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-o">++</span><span class="pl-n">i</span><span class="pl-p">){</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">y</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span> <span class="pl-o">==</span> <span class="pl-n">ans</span><span class="pl-p">)</span>
			<span class="pl-n">cout</span> <span class="pl-o">&lt;&lt;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;&lt;</span> <span class="pl-s">&quot; &quot;</span><span class="pl-p">;</span>
	<span class="pl-p">}</span>
	<span class="pl-k">return</span> <span class="pl-mi">0</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
</cpde></pre></div>